Check if there is a customer specific minimum. If so, that is the minimum for all of that customer’s orders.

If the customer’s minimum is empty, check the customer group's minimum. If that has a value, use it.

Finally, if both of the previous values are empty, use the account level minimum value.

When a buyer tries to checkout and has not met their minimum on HS Direct or HS Direct Mobile, the submit order button will be disabled and they will receive a message that they have not added enough to their cart to complete the purchase. You can see examples of both below: